And he wants to use that money to cut the prices of new hybrids and other cars that go farther on a gallon of fuel and pump fewer carbon emissions into the atmosphere.

The proposed "clean-car discount" -- which would be the first law of its kind in the nation -- would enlist car buyers in the fight against global warming by offering them a one-time bonus on cars the state identifies as environmentally friendly.

"It makes sense to give a financial incentive since most people just respond to their wallet," said shopkeeper Mary Ann McDonald in Sacramento. "If you make a practical vehicle more available, people will buy it."

But opponents are aghast at the idea of the state making buyers of SUVs and trucks subsidize hybrid purchases.

"This is a Robin Hood approach to things," said Fritz Hitchcock, a City of Industry vehicle retailer with dealerships across Southern California.

In Sacramento, Renee Cochran, a Ford Mustang-owning state worker, said she was not eager "to give my money to someone else if I want to buy a big car to go camping or to drag a boat."

The proposal is one of many ideas flooding the Legislature this year to address growing concerns about global warming. This one was introduced last week by Assemblyman Ira Ruskin (D-Redwood City).

He acknowledged that previous efforts to pass similar bills stalled in the Legislature, where automobile makers and dealers pack plenty of political clout. But this time could be different, thanks to the growing public concern about climate change, Ruskin predicted.

"People understand what needs to be done," he said. "They also want to play their part in doing the right thing. This gives consumers an incentive to buy clean cars that lower greenhouse gas emissions."

Giving rebates to clean-car buyers would be an easy way to fight global warming, contends the Cambridge, Mass.-based Union of Concerned Scientists, the principal backer of Ruskin's bill.

Shifting the mix of California's car and light truck fleet could remove an estimated 16 million tons of carbon dioxide and other greenhouse gases from the air, said Dan Kalb, the union's policy director. That's about one-tenth of the total reduction that the state seeks by 2020.

As proposed, the discount would take effect with new cars in the 2011 model year. Ruskin's bill specifies that the program would be "self-financing" with no outlays required by the state.

The level of rebates and surcharges would be based on state calculations of carbon emissions, and the amount of surcharges and rebates would range from $100 to $2,500.

Based on current emissions, the concerned scientists' group estimates, about 50% of new vehicles would receive a rebate of some kind, about 30% would face a surcharge and the rest would get neither.

But vehicle dealers and some owners counter that they don't like the government meddling with the extremely competitive new-vehicle market, even though the goal of curbing global warming is laudable.

They note that over the last year dealers have been selling fewer SUVs and more higher-mileage passenger cars.

"The marketplace is going to take care of this," said Peter K. Welch, president of the California Motor Car Dealers Assn. in Sacramento.

Carmakers agree that carrots in the form of tax breaks for buying hybrids or granting hybrid owners special access to carpool lanes are good ways to boost clean-car sales.

Slapping penalties on some buyers "would hurt a lot of Californians" who need larger vehicles, said Gloria Berquist, spokeswoman for the Alliance of Automobile Manufacturers in Washington.

The Ruskin bill would make it more costly to buy already expensive exotic sports roadsters, powerful luxury cars and 2-ton SUVs.

But it would still leave people with plenty of choices, proponents say. Some smaller SUVs and vans would be eligible for rebates, while other relatively fuel-efficient vehicles, including some full-size pickups, could be eligible for rebates or could be purchased by paying a surcharge.

Vehicles purchased by small businesses with fewer than 25 employees and less than $2.5 million in annual gross receipts would be exempt from the bill.

Ruskin calls approval of last year's landmark global warming bill "a tipping point" that proves that California lawmakers and voters, once again, are ready to lead the nation in supporting pioneering environmental laws.

He points to a year-old survey by national polling firm Fairbank, Maskin, Maullin & Associates that shows 60% of voters would support the idea of giving buyers discounts for clean cars and collecting surcharges for dirty ones.

To become law, the measure needs to win support from a majority of both houses of the state Legislature, which may be wary of angering SUV and pickup truck fans.

And even then, it still must be signed by Republican Gov. Arnold Schwarzenegger, a Hummer owner who has staked out an international leadership role in the campaign to limit climate change.

Schwarzenegger, who recently issued an executive order that requires oil companies to lower the carbon content of the fuels they sell, has yet to take a position on the Ruskin bill.

Getting a bill to the governor's desk will be tough, said V. John White, executive director of the Center for Energy Efficiency and Renewable Technologies, a Sacramento advocacy group. "Everybody is for incentives, but nobody is for penalties."